N-Chloramines

Despite the effectiveness of chloramine-T in this new method, removal of the toluenesulfonyl group from the newly introduced nitrogen substituent requires harsh conditions. The finding that the N-chloramine salt of tert-butylsulfonamide is also an efficient nitrogen source and the terminal oxidant for aziridination of... 

Reactions of potassium superoxide solubilized in apolar solvents with crown ethers (see Oxidation reactions, p. 356) are also frequently accompanied by elimination reactions. Thus, in DMSO solution, secondary alkyl bromides only yield olefins when treated with the K02 complex of dicyclohexyl-18-crown-6 (Johnson et al., 1978). Scully and Davis (1978) have studied the elimination of HC1 from N-chloramines with 18-crown-6-solubilized K02, KOH, and KOAc in ether solution (27). High yields of aldimines were obtained with K02,... 

For the substitution of the angular methyl groups in steroids five methods are known (a) homolysis of N-chloramines [Loffier-Freytag reaction (only C-18)] (b) oxidation of alcohols with lead tetraacetate (c) photolysis of nitrite esters (d) homolysis of hypochlorites (e) the hypoiodite reaction. ... 

B. Aminium Cation Radical Cyclizations from N-Chloramines and... 

A. N. Mirskova,T. I. Drozdova, G. G. Levkovskaya, M. G. Voronkov, Reactions of N-chloramines and N-haloamides with unsaturated compounds, Russ. Chem. Rev. 1989, 58, 250-271. 

An eight-stage synthesis of 2-methylbenzomorphan (115) from benzal-dehyde via diethyl benzylidene malonate (110) in 19% overall yield has been reported<52) (Scheme 4,17). The amino radical precursor, N-chloramine (111),... 

Aromatic amines and N-hydroxy derivatives Aliphatic epoxides and aromatic oxides Center of Michael reactivity Halogenated methanes N-chloramines... 

The preparation of an antimicrobial nylon 66 material by covalent bonding to biocidal cyclic N-chloramine moieties, including hydantoins, oxazolidinones, and imidazolidinones and its properties are considered. These cyclic materials were stable over at least 3 months dry storage, and after loss of activity by reaction with reducing Na thiosulphate, the activity was easily restored by exposure to free chlorine. Biocidal swatch tests showed that nylon fabrics containing N-chlorinated hydantoin functional groups produced a 7.2 log decrease in Staphylococcus aureus and a log 7.1 decrease in Escherichia coli after a contact time of only 10 minutes. The antimicrobial nylon should have many applications, e.g. in clothing, sutures, carpets, bmshes, etc. 

Chart 6. Radicals generated by photolysis of solutions of N-chloramines 36 and 37. 

Formation and Distribution of Organic N-Chloramines from the Ingestion of Chlorinated Drinking Water... 

Comparison of the products obtained by oxidation with CBT and the results of electrochemical oxidation of a mixture of 2-phenylindole with arylamines permits speculation that amination probably proceeds through formation of nitrenium cation from N-chloramine [86JCS(P1)607] (Scheme 115). 

The neutrophils adhere to the endothelium, block the capillaries and damage the endothelial integrity. Activated neutrophils produce reactive oxygen metabolites and release a variety of cytotoxic proteins, e.g. proteases, lactoferrin, and they also secrete the enzyme myeloperoxidase (MPO) which catalyzes the formation of potent cytotoxic oxidants such as hypochlorous acid (HOC1) from H202 and chloride ions and N- chloramines [172]. 

According to the original protocol [3] alkenes can be converted to racemic iV-tosyl protected 9-amino alcohols in the presence of catalytic amounts of osmium tetroxide using N-chloramine-T as the nitrenoid source and water as the hydroxyl source. However, unlike the AD-process, the aminohydroxylation of unsymmetrical alkenes can lead to two regio-isomeric products which was a drawback in... 

The high level of interest shown, in previous years, in the formation of nitrogen heterocycles by radical cyclizations has waned somewhat this year but two interesting applications of known procedures have appeared. Broka and Eng have shown that homolytic cyclization of the N-chloramine (131) efficiently yields the chloroindolizidines (132) and (133), with some stereoselectivity. Dechlorination of (132) and (133) proceeds very easily to yield gephyrotoxin 223AB (134) and the epimer (135). 93 The 3-alkyl-2-oxindoles (137) can be prepared in high yields by radical... 

Reaction of N-chloramines with aromatics [(153)-(155)] has been illustrated most recently with alkylaromatics by Clerici et al. (1974). Amination of aromatics is an electrophilic rather than free-radical... 

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